Alzheimer's risk varies among races

Age only universal factor, disease research shows

April 02, 2004|By William Hathaway | William Hathaway,HARTFORD COURANT

CROMWELL, Conn. - Japanese who live in Hawaii are at greater risk of getting Alzheimer's disease than Japanese living in Japan or in the mainland United States. Elderly Chinese may be more difficult to diagnose with dementia because of cultural practices and stigma attached to mental illness.

The devastation of dementia is global, but researchers are finding intriguing racial and ethnic variations to Alzheimer's, said Dr. Tiffany Chow, assistant professor of neurology at the University of Toronto who was the keynote speaker yesterday at the Connecticut Alzheimer's Education Conference.

Those differences may suggest new ways to prevent or treat the disease, Chow said.

There is one risk factor for Alzheimer's that is universal - age. The risk of Alzheimer's doubles every five years after the age of 60, Chow said. But other risk factors tend to vary, depending on racial background or where the person was born.

Chow said it is still a mystery why Hawaiian Japanese have higher rates of Alzheimer's than Japanese living elsewhere.

Studies have shown that blacks living in Indianapolis have twice the rate of Alzheimer's as Africans living in Nigeria.

One explanation for the difference is that blacks are almost 10 times more likely to have strokes or hypertension than their African peers, she said. Stroke and hypertension have turned out to be risk factors for vascular dementia and Alzheimer's, she said.

"Could diet be to blame? Sure," said Chow, who pointed out that Africans were more likely to be vegetarians.

One reason blacks are almost twice as likely as whites to develop Alzheimer's is that they are more prone to strokes.

"People don't seem to be too concerned with preventing strokes, but if you tell them this is a way to prevent Alzheimer's, their reaction might be different," Chow said.

Statin drugs, which lower cholesterol and are prescribed for cardiovascular disease, also may help prevent Alzheimer's and might be particularly beneficial for blacks, she said.

Doctors should also be aware of cultural differences that may affect the diagnosis of dementia.

Elderly Chinese women, for instance, tend to live with children, who seldom ask them to do much work, Chow said.

Also, in the Chinese culture it is considered an insult to suggest that a family member has any type of mental disability, she said.